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- Effect of three diets on the gametogenic development and fatty acid profile of Paracentrotus lividus (Lamarck, 1816) gonadsPublication . Raposo, Andreia; Ferreira, Susana; Ramos, Rodolfo; Santos, Pedro Moreira dos; Anjos, Catarina; Baptista, Teresa; Tecelão, Carla; Costa, José Lino; Pombo, AnaIn this study, the effects of three diets were investigated to enhance Paracentrotus lividus production for commercial purposes. P. lividus were fed ad libitum for 80 days with: diet A—fresh Codium tomentosum Stackhouse, 1797; diet B—formulated using a jellified mix of macroalgae and vegetables, including C. tomentosum (20%), Coralina sp. Linnaeus, 1758 (17%), cabbage Brassica oleracea var. capitata Linnaeus, 1753 (30%), carrot Daucus carota Linnaeus, 1753 (30%) and agar (3%) as a gelling agent. Diet C consisted of maize Zea mays Linnaeus, 1753 (56%) and New Zealand spinach Tetragonia tetragonoides (Pallas, 1781) Kuntze, 1891 (44%). Their effects on the gonadal and somatic growths, gonadosomatic index (GI) and gametogenesis were evaluated, as well as on the total lipid content and fatty acid composition of sea urchin's gonads. Diet A provided high values of eicosapentaenoic acid (EPA). Gonads of sea urchins fed with diet A were found mostly in growth and maturation stages of gametogenesis and showed the lowest lipid content. Sea urchins fed with diet B presented their gonads in the reabsorption stage and had the highest values of omega‐3 polyunsaturated fatty acids (PUFAs). Sea urchins fed with diet C were in the early stages of gametogenesis and had the highest values of lipid content, plus omega‐6 PUFAs. Once as an ingredient in a balanced mix with vegetables, C. tomentosum can be a key factor to the development of new promising high‐quality and low‐cost feed for P. lividus roe enhancement.
- Effect of three diets on the growth and fatty acid profile of the common ragworm Hediste diversicolor (O.F. Müller, 1776)Publication . Santos, António; Granada, Luana; Baptista, Teresa; Anjos, Catarina; Simões, Tiago; Tecelão, Carla; Fidalgo E Costa, Pedro; Costa, José Lino; Pombo, AnaThe polychaete Hediste diversicolor has a high physiological tolerance to extreme environmental factors, being easily farmed and reproduced in different types of conditions. Both in the field and under laboratory conditions, this worm can feed on different types of food. In order to highlight the potential of H. diversicolor for aquaculture, specific growth rate (SGR), daily growth rate (DGR), survival rate and fatty acid profile of juvenile worms, fed with three different diets, were assessed. The experiments were conducted using juvenile polychaete from a controlled reproduction with wild adults. H. diversicolor individuals were fed with two commercial diets, seabream dry feed (Aquagold) and semi-wet pellets for reared sole (Moist Sole), and with a non-processed diet consisting on mackerel's fillets (Trachurus trachurus). Juveniles fed with Aquagold had the highest final individual weight (0.89 ± 0.10 g). The SGR was higher in H. diversicolor fed with Aquagold and Moist Sole, (6.49 ± 0.30% d−1 and 6.54 ± 0.06% d−1, respectively. The highest DGR was observed for juveniles fed with Aquagold (0.146 ± 0.02 g d−1). The survival rate of ragworms under different treatments ranged from 96 to 100%. Regarding the protein content, the Moist Sole diet provided the highest percentage of protein in the reared worms (8.87%). Results showed that the total fat content of the diets was reflected in the fat content of the reared worms. The Moist Sole diet treatment had the highest fat content (2.25%) and individuals fed with seabream dry feed showed similar results (2.18%), while the lowest percentage was observed for the mackerel diet (0.85%). According to the fatty acid profile, the major fatty acids found in the juveniles fed with the three different diets were palmitic (C 16:0), with a higher value in the individuals fed with mackerel's fillets. Oleic (C 18:1 n9), eicosapentaenoic (C 20:5 n3), docosahexaenoic (C 22:6 n3) and stearic (C 18:0) acids presented high values in H. diversicolor fed with all the experimental diets. Statement of Relevance: The common ragworm Hediste diversicolor is a potential high quality fatty acids source for reared fish and shrimp. Previous studies suggested that diet could be a relevant factor affecting the fatty acid composition of this polychaete (Luis and Passos, 1995). This study aimed to assess the effect of different diets on growth and survival of common ragworms juveniles (H. diversicolor), as well as the fatty acid profile and protein content in their tissues, aiming to find an appropriate diet to be used in commercial aquaculture.
- Insight into aquaculture's potential of marine annelid worms and ecological concerns: a reviewPublication . Pombo, Ana; Baptista, Teresa; Granada, Luana; Ferreira, Susana; Gonçalves, Sílvia C.; Anjos, Catarina; Sá, Erica; Chainho, Paula; Cancela Da Fonseca, Luís; Fidalgo E Costa, Pedro; Costa, José LinoPolychaetes are marine annelid worms that can contribute to aquaculture diversification. Its culture has been viable, and commercially attempted, but intensive production has progressed only in few countries around the world. In the countries with no production, marine polychaetes are imported or harvested. A strong and sustained research investment provided to a better understanding of the nutritional requirements and reproduction of some species. Recent studies showed new technical improvements, which can lead to an important progress in productivity and give a new impetus to the polychaete production. Some marine worm species were identified as good candidates for integrated multitrophic aquaculture. The development of cost-effective aquaculture techniques for marine annelid worms is essential to ensure a balance between commercial interests and the preservation of ecosystems. The influence of polychaete aquaculture on the environment and vice versa raise important concerns related to ecological security and sustainability of this activity. This review focus on the main technical improvements and advances that have been made in areas as diverse as: aquaculture potential of polychaetes, reared species, main species used worldwide, and highlights biological and ecological concerns, important challenges and recommendations.